PEORIA — Former Charter Oak Primary School Principal John Wetterauer has submitted his resignation to Peoria School District 150, according to District 150 spokesman Chris Coplan.

Wetterauer had been on medical leave since January after he was removed from Charter Oak in the wake of the district’s investigation into standardized testing irregularities at the award-winning school.

District 150 board members approved Superintendent Grenita Lathan’s recommendation to place Wetterauer on special assignment at Woodruff Career and Technical Center. Wetterauer never reported to Woodruff. Instead, he requested medical leave based on his doctor’s advice.

Wetterauer did not return calls for comment.

The district’s investigation alleged a long-standing pattern of testing irregularities committed by special education teachers at Charter Oak that Wetterauer should have been aware of and corrected. He failed to train teachers on how to properly administer the ISAT, or Illinois Standards Achievement Test, according to the investigation. The Illinois State Board of Education is investigating the issue.

Two special education teachers were transferred and given remedial warnings.

Parents of Charter Oak students organized an unsuccessful, but intense, lobbying campaign to get Wetterauer reinstated as principal. Their efforts evolved into Change150, a coalition that has vowed to change the make-up of District 150’s board.

Pam Adams can be reached at 686-3245 or padams@pjstar.com. Follow her on at Twitter @padamspam.